1. Field of the Invention
The present invention relates to an X-ray detection signal processing apparatus for and a method of receiving a signal, which has been generated from an X-ray detector and has subsequently been passed through a preamplifier, to output a signal of a pulse height proportional to an energy of X-rays incident on the X-ray detector.
2. Description of Related Art
In the X-ray fluorescence analysis, for example, a signal generated from an X-ray detector has hitherto been differentiated by a preamplifier of a pulse reset type or a register feedback type for the purpose of removing a direct current component and, accordingly, it contains a component that is decayed by a differential time constant. If such an analog signal in the form as presented is converted into a digital signal and is then supplied to a pulse height analyzer, the gain and the base line tend to change and, therefore, conversion into the digital signal has carried after a treatment, in the analog signal processing apparatus, had been effected to remove influences that might be brought about by the component tending to be decayed by the differential time constant, and is then supplied to the pulse height analyzer. In this connection, see, for example, the non-patent documents 1 and 2 listed below. In this instance, the influences brought about by the component tending to be decayed by the differential time constant includes a change in final gain, that results from a change of a convergence value of a signal tending to be decayed by the differential time constant, and a change in final base line that results from a change of the differential time constant itself. Also, the digital signal processing apparatus in which a treatment similar to that discussed above is carried out on a digital basis.
In this connection, see the patent document 1 listed below.
[Prior Art Literature]
[Patent Document 1] JP Patent No. 4083802
[non-Patent Document 1] Y. Koshi and K. Sato, “Enerugi Bunsan-gata Ekkusu-sen Bunseki: Handoutai Kenshutsuki-no Tsukaikata (Energy Dispersive X-ray Analysis: How to Use the Semiconductor Detector)”, Nippon Bunko Gakkai Sokuteihou Sirizu No. 18 (Spectroscopical Society of Japan Measurement Method Series No. 18), first edition, Kabushiki Kaisha Gakkai Shuppan Senta, Jun. 30, 1989, pp. 30-33.
[non-Patent Document 2] Helmuth Spieler, “Semiconductor Detector Systems”, Series on Semiconductor Science and Technology No. 12, Oxford University Press Inc., 2009, pp. 175-179.
It has, however, been found that the analog signal processing apparatus of the kind referred to above tends to become complicated in structure, requiring several hundred component parts and, also, requires a complicated adjustment. On the other hand, the digital signal processing apparatus of the kind referred to above, although simple in structure, is incapable of sufficiently removing the change in the final base line resulting from the change of the differential time constant itself.